
var websocket = null;
var username = localStorage.getItem("name");

//判断当前浏览器是否支持WebSocket
if ('WebSocket' in window) {
	websocket = new WebSocket("ws://"+document.location.host+"/WebChat/websocket/" + username);
} else {
	alert('当前浏览器 Not support websocket')
}

//连接发生错误的回调方法
websocket.onerror = function() {
	setMessageInnerHTML("WebSocket连接发生错误");
};

//连接成功建立的回调方法
websocket.onopen = function() {
	setMessageInnerHTML("WebSocket连接成功");
}

//接收到消息的回调方法
websocket.onmessage = function(event) {
	setMessageInnerHTML(event.data);
}

//连接关闭的回调方法
websocket.onclose = function() {
	setMessageInnerHTML("WebSocket连接关闭");
}

//监听窗口关闭事件，当窗口关闭时，主动去关闭websocket连接，防止连接还没断开就关闭窗口，server端会抛异常。
window.onbeforeunload = function() {
	closeWebSocket();
}

window.onunload=function(){
	closeWebSocket();
}

//关闭WebSocket连接
function closeWebSocket() {
	websocket.close();
}